November 23, 2007 | David F. Coppedge

No Salt, Please: Europa Life Needs It Bland

Salt may taste good on human food, but for life trying to emerge in the sea, it is toxic.  Astrobiologists have long wondered if life could exist at Jupiter’s moon Europa, where an ocean is believed to exist miles deep under the icy crust.  They must have been presuming the water is pure, but an article on Astrobiology Magazine, a NASA website, says that Europa’s ocean could be saturated with salt.

The amount of salts in the ocean also could be stressful for life.  [Kevin] Hand [Jet Propulsion Laboratory] says the Galileo magnetometer results indicate Europa’s ocean could be nearly saturated in either sodium chloride or magnesium sulfate.
    “If you’ve got a salt-saturated ocean, that doesn’t bode well for the origin of life,” says Hand.  “Some of the processes that lead toward the generation of polymers or the stringing together of genetic base pairs are inhibited by high salt concentrations.  That said, there are terrestrial halophiles, salt-loving microbes, that could survive in the ocean we propose.”

Terrestrial (earth-based) halophiles (salt-lovers), however, did not originate in a salty sea, according to evolutionary theory.  Presumably, they developed the ability to deal with salt long after life arose.

Recall the 09/17/2002 paper that taught us to avoid salt at all costs when modeling the origin of life in a primordial soup.  Salt of any kind is very effective at dismembering fatty acids needed for cell membranes and preventing nucleotides from linking up (assuming they could even form in water; see 11/05/2004).  Monard et al had no answer, but just pointed out that this was a “crucial piece of information” for astrobiologists theorizing about how life might have formed in a random sea of chemicals.
    Yet hope springs eternal.  You can almost hear the hand-wringing in the Astrobiology Magazine article.  They just admitted that the presence of salt does not bode well for the origin of life.  They’re thinking, But… if life DID originate somehow, maybe it could get along just like the halophiles on Earth manage to do.  Foul.  It didn’t.  Salt tosses life out of the equation.  You can’t get there from here.
    While we’ve got them pinned to the floor, let’s put the squeeze on by asking another pertinent question.  What is the likelihood that the Earth’s early oceans, filled with runoff from the torrential rains and upheavals for two billion years after its hellish birth (11/01/2007), were pure and soft as spring waters?  Salt is bad for astrobiology here, too.  If salt was present, you may as well become a creationist now, because Charlie is out before he gets to the starting gate.  Sorry for the mixed metaphors of wrestling and horse racing, but you get the point.  Charlie’s horse may enjoy a salt lick, but salt licks astrobiology like a Charlie horse.

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